Gas anchor for oil wells



Oct. 5 61926.

C; T. M COY GAS ANCHOR FOR'OIL WELLS Filed Feb. 19, 1925 Patented Oct.5, 1926. I

MAN E. CONKLIN AND ONE-FOURTH 'lO RALPH B. BLODGET,

CALIFORNIA.

CLIFFORD T. MCCOY, OF TORRANGE,

CALIFORNIA, ASSIGNOR OF ONE-FOURTH TO NOR- BOTI-I 011 LOS ANGELES,

GAS ANCHOR FOR OIL WELLS.

Application filed February 19, 1925. Serial No. 10,307.

This invention relates to improvements in gas anchors for oil wells.

tively separate the majority of gas from the oil when pumping in an oilwell, and which will thoroughly mix such gas as will not separate fromthe oil and any the oil, so that in this manner mud, which enter thepump, oughly mixed and will not action.

floating mud with oil, gas and will be thorhinder pump A further objectof the invention is to provide an improved gas anchor adapted toseparate the majority of be pumped to mix enters the pump separatingmost of the oil before it the sand 1 as from the oil to thoroughly thefluid which and to provide means for n the oil from enters the pump.

A still further object of the invention is to provide an improved sandtrap for a gas anchor.

following detailed descriptionand pointedi reference is had out in theappended claims,

to the accompanying drawings for an illustrative embodiment wherein ofthe invention,

Figure 1 is a vertical section througha well, showing in section theanchor;

Fig. 2 is a view similar to- Fig. 1, showing improved gas the sand trapin the gas anchor as being dumped;

3 is a-horizontal stantially on the line 3-3 oi section taken sub- 7Fig. 1;

Fig. 1 is a section taken on the line H 01. Fig. 3

Fig. 1;

Fig. 5 is a view taken on the line 5--5 of Fig. 6 is a perspective viewshowing how the upper section of the outer tube of the gas anchor isconstructed; and

Fig. 7 is a perspective view, showing how the inner tube of structed.

Referring to wherein similar the gas anchor is con the accompanyingdrawings reference characters designate similar parts throughout, thewell hole is indicated at 10, in which there is dlsposed the well casing11. The pump barrel 1s 1ndicated at 12, upon the lower is mounted'theconvent-iona end of which 1 coupling 13 having a tapered interiorproviding aseat tor the standing valve seat 14;. The standing valveiisshown as provided with a ball closure 15 movable within a cage 16. Allof the above described structure is conventional in the ordinary deepwell pump.

Thegas anchor consists of'aninner tube U which is threaded into thelower end of the coupling 13. This tube is of a length slightly lessthan the length of an ordinarv pump tubing section. The lower end of theinner tube 17 is notched to provide a plurality of fingers 18 for apurpose hereinafter to be described.

About the inner tube 17 there is disposed an outer tube 19 ofapproximately the same length as the inner tube 17 and this outer tubeis notched adjacent its upper end to provide a plurality of fingers 20.The fingers 20 are preferably welded or may be otherwise secured uponthe exterior otthe inner tube 17, adjacent its top; and in a similarmanner the fingers 18 are welded or otherwise secured upon the interiorof the outer tube 19. The fingers 20 cooperate with the inner tube 17 toform a plurality of apertures, through which oil within the casing 11may be admitted to the interior of the outer tube 19; and in a similarmanner the'iingers 18 cooperate with theouter tube 19 to form aperturesenabling the oil, which enters between the fingers 20, to passclownwardly within the outer tube.

A pipe 21 is threaded into the standing valve seat 14 and this pipe isdisposed within the inner tube 17 and extends a considerable distancebelow the lower end of the in.- ner tube 17. The bottom of the pipe 21is preferably closed, and adjacent its bottom the pipe 21 has formedtherein a plurality of perforations 22. The outer tube 19 may be formedof a plurality of pipe sections, which may be connected together as bycollars 23.

Adjacent the bottom of the outer tube 19 there is disposed asand trap,generally designated at 2 1. This sand trap consists of a pin or rod 25extending diametrically across the outer tube 19. Semi-circular doors 26and 27 are provided with lugs 28 which are bent about the pin 25 so asto hinge the doors to the pin. Between the lugs 28 there are disposedcoil springs 29. which are arranged about the'pin 25, and these springshave arms 30 and 31 which bear upon the under side of the doors 26' and2? respectively. The springs 29 urge the doors 26 and 27 into anapproximately horizontal position within the outer tube 19, so as toclose this tube. These doors are cap-able of being pushed downwardlytoward each other beneath the pin against the action of the springs 29so as to open the tube 19 and allow material to pass therethrough.

The operation of the device is as follows: Oil, gas, sand, floating mudand other material passes upwardly within the casing 11. As it reachesthe top of, the outer tube 19, the oil, mud and sand enter the outertube 19 by passing downwardly between the fingers 20. The gas in the oiltends to rise vertically with it within the casing 11, and as the oiland other liquid carryin sand and the like must pass downwardly withinthe outer tube 19, the majority of the gas is separated from the wellfluid at this point. As the oil, floating mud and sand pass downwardlybetween the outer tube and the inner tube, these materials pass throughcomparatively constricted passages, and because of the small dimensionsof the passages, the flow is at a very high velocity. This movement ofthe fluid causes the oil and floating mud to be broken up and to bethoroughly mixed. Any gas, which is not separated from the oil at thetop of the outer tube 19 and which passes downwardly between the outertube and the inner tube, is also thoroughly m'xed in the oil, and inthis manner gas pockets are effectively broken up. As the fluid passesdownwardly between the fingers 18, the passages through which the fluidpasses are of larger dimensions and because of the larger size of thepassages, the velocity, with which the oil flows downwardly, is somewhatslower. When the velocity of the fluid is lowered to this extent, thesand, which is within the oil, tends to settle out and fall within thetube 19 and settle upon the sand trap 24:. lhe oil, floating mud andgas, which are thoroughly mixed and which have the larger portion of thesand removed, enters the pipe 21 through the perforations 22, and passesupwardly within the pipe 21 through the standing valve and into thepump. As the weight of the sand upon the sand trap increases, the doors26 and 27 are forced downwardly upon the pin 25 against the action ofthe springs 29 so as to allow the sand, which has accumulated, to falldownwardly through the bottom of the outer tube 19. When the sand, whichhas accumulated, has been dumped,the springs 29'swing the, doors back upinto their original position.

I have found by experience that it is impractical to employ'a pipe forthe outer tubev 19, whichis less than three inches in diameter for thereason that smaller sized pipes,

which have sand traps or similar devices for allowing sand to settletherein, will allow the sand to bridge across the pipe, and in thismanner stop or plug it up. Larged sized pipes may be employed, if sodesired, but it is impractical to employ a pipe for the outer tube,which is less than three inches in diameter. In using a three inch outertube, 1 preferably employ a two inch pipe for the inner tube 17, and aone inch pipe for the pipe 21. The lower end of the pipe 21 should beabout the length of one pipe section below the lower end of the innertube 17, so that the fluid passes downwardly, the sand will have ampleopportunity to settle out of the oil. The lower end of the pipe 21should therefore be approximately twenty feet or more below the fingers18. In practice the sand trap 24 is located at least twenty feet belowthe lower end of t is pipe 21, or, in other words, the length of a pipesection. In this manner a tall column of sand may accumulate upon thesand trap 24:, and by its own weight will force the doors 26 and 27downwardly so a todump. By allowing such a distance in which sand mayaccumulate, dumping of the trap can nearly always be effected, and theaccumulated sand will not cover up the perforations 22 before dumpingthe trap. In case the sand should bridge across the outer tube 19, it ispossible by pulling the pump and lifting the standing valve to allow thepressure developed by the column of fluid within the pump tubing to passdownwardlyv directly through the inner tube 17 and thus force theaccumulated send through the sand trap 24.

The lower end of the outer tube 19 is prel erably beveled or slightlyrounded off, so that when the device is lowered within the well casing,it will not tend to catch upon a collar or other obstruction within thewell casing and damage the gas anchor or the casing. The pipe 21, whichis lowered within the inner and outer tubes, is lowerec by means of thestanding valve and the sucker roc s.

It will be understood that various changes in the detail of construction'inay be .e without departing from the spirit scope of the invention asdefined. by the appended claims.

I claim:

1. A gas anchor for oil wells comprising an inner tube adapted to beconnected to the pump barrel, an outer tube disposed about said innertube and extending therebelow, fingers formed upon the upper end of saidouter tube and secured to said inner tube so as to cooperate therewithto form apertures, fingers formed upon the lower end of inner tube andsecured to said outer tube so as to, cooperate therewith to formapertures, anda pipe adapted to be secured to the standing valve and tobe disposed within said inner tube and to extend materially therebelow.

2. A gas anchor for oil wells comprising an inner tube adapted to beconnected to the pump barrel, an outer tube disposed about saidinnertube and extending therebelow, fingers formed upon the upper end ofsaid outer tube and secured to said inner tube so as to cooperatetherewith to form apertures, fingers formed upon the lower end of saidinner tube and secured to said outer tube so as to cooperate therewithto form apertures, a pipe adapted to be secured to the standing valveand to be disposed within said inner tube and to extend materiallytherebelow,

and a sand trap mounted in said outer tube a considerable distance belowthe lower end oi said pipe.

3. A gas anchor for oil wells comprising an inner tube adapted tobeconnected to the pump barrel, an outer tube disposed about said innertube and extending therebelow, fingers formed upon the upper end of saidouter tube and secured to said inner tube so as to cooperate therewithto form apertures, fingers formed upon the lower end of said inner tubeand secured to said outer tube so as to cooperate therewith to formapertures, and a pipe adapted to be secured to the standing valve and tobe disposed within said inner tube and to extend materially therebelow,said pipe having its lower end closed and being provided withperforations which are located a considerable distance below the lowerend of said inner tube.

A gas anchor for oil wells comprising an inner tube adapted to beconnected to the pump barrel, an outer tube disposed about said innertube and extending therebelow, fingers formed upon the upper end of saidouter tube and secured to said inner tube so as to cooperate therewithto form apertures, fingers formed upon the lower end of said inner tubeand secured to said outer tube so as to cooperate therewith to formapertures, a pipe adapted to be secured to the standing valve and to bedisposed within said inner tube and to extend materially therebelow,said pipe having its lower end closed and being provided withperforations which are located a considerable distance below the lowerend of said inner tube, and a sand trap mounted in said outer tube aconsiderable distance below the lower end of said pipe.

5. A gas anchor for oil wells comprising an inner tube adapted to beconnected to the pump barrel, an outer tube disposed about said innertube and extending therebelow, fingers formed upon the upper end of saidouter tube and secured to said inner tube so as to cooperate therewithto form apertures, fingers formed upon the lower end of said inner tubeand secured to said outer tube so as to cooperate therewith to formapertures, a pipe adapted to be secured to the standing valve and to bedisposed Within said inner tube and to extend materially therebelow,said pipe having its lower end closed and being provided withperforations which are located a considerable distance below the lowerend of said inner tube, a sand trap mounted in said outer tube aconsiderable distance below the lower end of said pipe, said sand trapcomprising a pin extending diametrically across the outer tube,semicircular doors hinged upon said pin adapted to swing downwardlytoward each other below said pin, and spring means for urging said doorsinto such position as to close said outer tube.

6. In a gas anchor for oil wells, a sand trap comprising a tube, a pinextending diametrically across said tube, doors hinged upon said pinadapted to swing downwardly below said pin so as to open said tube, andspring means for urging said doors into an approximately horizontalposition so as to close said tube.

7 A gas anchor for oil Wells comprising an inner tube adapted to beconnected to the pump barrel, an outer tube disposed about said innertube and extending therebelow, fingers formed upon the upper end of saidouter tube and secured to said inner tube so as to cooperate therewithto form apertures, fingers formed upon the lower end of said inner tubeand secured to said outer tube so a CLIFFORD T. MoCOY

